On Wed, 21 Aug 2019 13:57:06 -0400 Vivek Goyal <[email protected]> wrote:
> From: Sebastien Boeuf <[email protected]> > > On MMIO a new set of registers is defined for finding SHM > regions. Add their definitions and use them to find the region. > > Cc: [email protected] > Signed-off-by: Sebastien Boeuf <[email protected]> > --- > drivers/virtio/virtio_mmio.c | 32 ++++++++++++++++++++++++++++++++ > include/uapi/linux/virtio_mmio.h | 11 +++++++++++ > 2 files changed, 43 insertions(+) > > diff --git a/drivers/virtio/virtio_mmio.c b/drivers/virtio/virtio_mmio.c > index e09edb5c5e06..5c07985c8cb8 100644 > --- a/drivers/virtio/virtio_mmio.c > +++ b/drivers/virtio/virtio_mmio.c > @@ -500,6 +500,37 @@ static const char *vm_bus_name(struct virtio_device > *vdev) > return vm_dev->pdev->name; > } > > +static bool vm_get_shm_region(struct virtio_device *vdev, > + struct virtio_shm_region *region, u8 id) > +{ > + struct virtio_mmio_device *vm_dev = to_virtio_mmio_device(vdev); > + u64 len, addr; > + > + /* Select the region we're interested in */ > + writel(id, vm_dev->base + VIRTIO_MMIO_SHM_SEL); > + > + /* Read the region size */ > + len = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_LOW); > + len |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_LEN_HIGH) << 32; > + > + region->len = len; > + > + /* Check if region length is -1. If that's the case, the shared memory > + * region does not exist and there is no need to proceed further. > + */ > + if (len == ~(u64)0) { > + return false; > + } I think the curly braces should be dropped here. > + > + /* Read the region base address */ > + addr = (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_LOW); > + addr |= (u64) readl(vm_dev->base + VIRTIO_MMIO_SHM_BASE_HIGH) << 32; > + > + region->addr = addr; > + > + return true; > +} > + > static const struct virtio_config_ops virtio_mmio_config_ops = { > .get = vm_get, > .set = vm_set, Reviewed-by: Cornelia Huck <[email protected]>
